Manufacture of gramophone records



M3) 12, 1931- N. PEMBERTON-BILLING 1,

MANUFACTURE OF GRAMQPHONE RECORDS Filed Nov. 17, 1926 g ll llf f Iizvezzzor:

Patented May 12, 1931 NOEL PEMBERTON-BILLING, TWICKENI'XAM,

MENTS, TO AMERICAN AND,DO1VIZI TION LONDON, ENGLAND i ENGLAND, JASSIGNOR', BY MEs NE ASSIGN- S UNBREAKABLE RECORDS LIMITED, OF

Iv'lTANUFACTUEE 0E GRAlEOPI-IONE RECORDS Application filed-November 17, 1926, Serial No. 148,958, and in Great Britain November 24, 1925.

This invention consists in improvements in or relating to the manufacture of gramophone records and is particularly adapted, although not limited to records having a certain amount of flexibility in their finished state. 1

It has been hitherto proposed to coat a paper, cardboard or like base with record material in a fluid state and thereafter to dry the coated base and subsequently to ap ply the record impressions to the blank thus produced.

Diificulty has been experienced hitherto in coating successive discs or sheets of paper, cardboard or other suitable material constituting the base aforesaid with record material from-a batch of that material in such a manner as to obtain a uniform coating throughout a large number of sheets or discs which the batch of material is suflicient to treat. The invention provides improved means for coating such base material whereby these difiiculties are Overcome. -According 'to the invention said means comprises in combination a roller or equivalent device for applying the coating to the discs or sheets aforesaid and means for continually agitat ing the liquid record material as it is supplied to the roller or the like. Conveniently agitation is provided by means which continually circulates the record material from a supply to the roller or the like and collects thesurplus material and passes it back to the supply for re-circulation.

In order that the invention may be more clearly understood one preferred embodiment will now be described with the aid of the accompanying drawing which is a purely diagrammatic illustration of the coating mechanism.

The base material may be in sheets or discs of any preferred size and these sheets or discs are fed on to an endless band 10 which travels in the direction of the arrow towards a roller 11. Each sheet is gripped at its leading edge by means of gripping devices 21 on the roller 11 such as are employed on rollers for varnishing machines.

A second roller 12 is mounted to press against the sheet of materlal as it 1s carried past the roller 12 by the roller 11. The roller 12 dips into a pan 13 to which a constant supply of record material is fed through a pipe 14: from a supply cylinder 15.

The latter may comprise the main receiver for the record material or may be in continuous communication therewith and is provided with a reciprocating'piston 16, indicated as operated by the eccentric and strap 17. The piston 16 has a relatively short stroke and when moved downwardly pumps record material through the pipe 14 into the pan '13 from which it is picked up by the roller 12. Surplus material passes from the outlet 18 back into the cylinder 15 so that the record material is kept in a state of constant agitation;

Although one outlet 18 only is illustrated it will be understood that the pan, which is seen end on in the drawing, has several sucit' 7 outlets arranged along its length all ofwhich feed back into the cylinder 15 or into the res. ervoir with whichthe cylinder 15 is in communication.

By the "continuous agitation'and circula tion of the record material the latter retains a homogeneous condition throughout the entire period of its use. V

Each coated sheet of base material after leaving the roller 12 is passed on tothe second endless band 19 and on this band is passed through a drying chamber'QO where the coating is dried at a temperature of say160 C. The base iscoated in this manner as many times as is desired to apply the required thickness of coating material, in successive layers, tothe surface of the base. Preferably only one side of the base is intended to receive a record impression and this wi'llbc coated with say three or four thicknesses of material while theother side of the base will be given a single coating only so that it'may,

by means of this coating, be caused to adhere to a similarly coated surface of a second base when preparing a compound blank to pro duce a double-sided record.

It is'sometimes preferred to supply the liquid record material from the pipe 14 to a spraying. device which distributes the mate rial uniformly or substantially uniformly over the whole length of the coating roller or such a spraying device may be used in addition to the supply leading directly into the pan 13. If the spraying device only is employed it is preferred to feed the record inaterial at such a rate that a certain amount remains always in the bottom of the pan sulficient to enable the coating roller always to dip into the record material therein.

The discs or sheets of base material can be coated on one or both sides. They may be used singly or in pairs with or without a layer of filling material between pairs of them. In the latter case the filler may be built up from a plurality of blanks of which the coating can be ofrecord material or other adhesive such, for example, as a shellac solution. It is only necessary to coat what are to be the record surfaces with record material and to subject those surfaces to subsequent treatment so that record impressions may be applied to the blank thus produced.

In order to obtain consistent results it may be found desirable to control the viscosity of the fluid-record material by regulating the temperature of that material during the coat ingoperation. This may be eifectedfor 6X- ample by heating the mixture in the pipe which delivers it to the trough from which it is picked up by the coating roller. Al-

ternatively the temperature may be under constant observation by the provision of a thermometer in some convenient portion of the apparatus and the attendant, by observing any change which may occur in the temperature can regulate the heating means. The heating may be eifected by elec tricity, steam or by direct application of hot products of combustion to the sump or to any other preferred part of the apparatus and, if

necessary, a thermostatic device may be em ployed for automatically regulating the temperature.

I claim Apparatusrfor coating gramophone record bases with liquid record material, comprising in combination means to convey the bases separately past a coating device for applyig the coating to the bases, which device is supplied with coating material in excess of that required for coating the bases, means including a pump for agitating the liquid record material and for continually circulating it between a supply reservoir and the coating device, a heating chamber for drying the coated bases, and means for conveying said bases from the coating device through said chamber.

In testimony whereof I affix my signature. NOEL 'PEMBERTON-BILLING. 

